That screenshot was taken just before 4pm PST, i.e. just before 0000 UTC. That shows KittehHead's votes for the month, which is the same as for the day since it's March 1st. Just to be sure it wasn't that SE had the time wrong, I tried upvoting something and got the expected "Daily Vote Limit Reached, Please Vote Again in 6 minutes."

@RebeccaChernoff It seems like the simplest solution, I'd hate to tie up any worthwhile SE Valued Associate time when simply wiping WesleyDavid's existence out of all SE databases would do it!
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WardMar 6 '12 at 23:15

This appears to be correct. Today, I've cast 36 votes in total (taken from the user info popup), but got a message saying I had 5 left for today. One of the posts I voted down ended up being deleted.
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lunboksMar 3 '12 at 16:13